Electrical connectors have long been known in the art. For example, U.S. Pat. No. 3,160,457, to Walter Fischer, patented Dec. 8, 1964, entitled "Electrical Connecting Device", issued on an application filed in the United States on Nov. 30, 1962 is a good example of such connectors. The Fischer '457 Patent, incorporated herein by reference, discloses a detachable parallel electric current path connecting device, which is formed of two parts, each adapted to be connected to a respective electrical conductor, one of these parts carrying at least one male contact and the other carrying at least one corresponding female contact. This configuration has served the industry well through the years as a reliable, effective connector.
Although the above configuration includes advantages, there is always room for improvement, including improvements in how such connectors are used in various applications. For example, as upgrades are made to electrical equipment including such connectors, for safety and/or regulatory reasons it may be necessary that certain cross-system connections between system versions be prevented while other cross-system connections are allowed.
As an example, one may assume a typical system scenario in which a hand tool is attached to a control box though an electrical cord having a detachable connection therein. An upgrade is then made by the system manufacturer to both the hand tool and the control box. This results in the existence in the field of original hand tools configured to connect with original control boxes, as well as upgraded hand tools configured to connect with upgraded control boxes. If there is no desire to allow any interaction between the two systems, prior art connecting schemes can be used to provide different mating connections similar in concept to the different wall plug configurations used between 110 and 220 Volt AC systems. In other words, an original plug only fits an original receptacle, and an upgraded plug only fits an upgraded receptacle. There is no "cross-system connectivity".
However, there may be a desire by the system manufacturers to allow, as an example, the original hand tools to connect with the upgraded control boxes, but to prevent the upgraded hand tools to connect with the original control boxes. This need cannot be met by the known prior art.
Therefore, there is a need in the art for an electrical connection configuration which can be used to upgrade an electrically-connected two part system to allow for a "first" component of the original system to interact with either a "second" component of the original system or an alternate (i.e. upgraded) "second" component being part of an alternate system, while restricting connection between the "first" component of the alternate system to connection only with the "second" component of the alternate system, and while preventing connections between the "first" component (e.g., a hand tool) of the alternate system and the "second" component (e.g., a control box) of the original system.